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A sequence of six tones with a semitone in the middle, the others being whole tones, that was used in medieval music.
[Medieval Latin hexachordum, from Latin hexachordos, having six strings or stops : Greek hexa-, hexa- + Greek -khordos, string, note (from khordē; see cord).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
(Music, other) (in medieval musical theory) any of three diatonic scales based upon C, F, and G, each consisting of six notes, from which solmization was developed
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
a diatonic series of six tones having a half step between the third and fourth tones and whole steps between the others.
[1685–95; < Late Greek hexáchordos having six strings]
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